The present invention relates to construction equipment, such as cranes, which must be disassembled into a number of separate components to be transported between job sites, and more particularly to a method and an apparatus for self-assembling and self-disassembling.
Construction equipment, such as cranes or excavators, often must be moved from one job to another. Moving a crane or excavator can be a formidable task when the machine is large and heavy. For example, highway limits on vehicle-axle loads must be observed and overhead obstacles can dictate long, inconvenient routings to a job site.
One solution to improving the mobility of large construction machines, such as cranes, is to disassemble them into smaller, more easily handled components. The separate components can then be transported on separate trailers to the new job site where they are reassembled.
The typical practice has been to use an assist crane to disassemble the crane into the separate components. The assist crane is then used to load the components onto their respective transport trailers. Once at the new job site, another assist crane is used to unload the components and reassemble the crane. As the separate components for a large capacity crane can weigh as much as 80,000 lbs., the capacity of the assist crane required represents a very significant transport expense.
As a result, designers have attempted to develop self-handling systems for assembling and disassembling cranes. However, self-handling systems developed thus far have been limited to smaller capacity cranes which need to be disassembled into only a few components. Self-handling systems for larger capacity cranes, which must be disassembled into numerous components, have yet to be developed. The primary reason for this is that the boom on a larger capacity crane must be unrigged and disassembled from the crane, thus limiting the use of the boom for further disassembly.
Prior art self-handling systems also have the disadvantage of requiring the boom hoist rigging to be unrigged from the equalizer.